Using earlier versions of MIPL we observed a few problems with medium to long term usage. In brief these concerned the kernel failing to add IPv6 routes and needing to be rebooted and unsolved negative binding acknowledgements sent by the HA on MN binding updates. However, with MIPL 1.0 and further versions we have not noticed these problems.

Multiple interface support works (we tested for example handovers between Bluetooth and 802.11 access networks with a MIPL client switching the priority of the interfaces), but sometimes when both interfaces receive router advertisements at short intervals (around 1 second), there are spurious switches between the interfaces, though the interface preference is not changed. This might be a problem with how the router advertisement lifetime is handled in the MIPL implementation. If the router advertisements are received at a slightly lower rate (2 seconds), these interface changes do not occur.

In our testbeds, we have not been able to test IPSec authentication between the MN and HA. This is because authentication and authorization of MIPv6 messages between the MN and HA is missing in 2.4 series kernels. This will not be supported by the MIPL team in the 2.4 kernels unless someone backports the IPSec in 2.6 kernels to 2.4 kernels. However, MIPL for 2.6 series kernels (MIPL v2.0 onwards) will have IPSec support from the start.

Another problem which was observed is that the routing table is sometimes not correctly updated. So old routes from visited networks remain in the routing table.